Fabrication of novel iminodiacetic acid-functionalized carboxymethyl cellulose microbeads for efficient removal of cationic crystal violet dye from aqueous solutions.

Novel anionic adsorbent microbeads were fabricated based on surface functionalization of p-benzoquinone-carboxymethyl cellulose (CMC-PBQ) activated microbeads with iminodiacetic acid (IDA). The developed IDA@CMC-PBQ microbeads were characterized by FT-IR, TGA, SEM, XPS and zeta potential analysis tools. Ion exchange capacity measurements proved the successful generation of extra carboxylic groups on the surface of IDA@CMC-PBQ microbeads with a maximum value reached 3.984 meq/g compared to 1.32 meq/g for neat CMC microbeads. The fabricated microbeads were tested for the removal of cationic crystal violet (CV) dye from aqueous solutions under various adsorption conditions. The results clarified that the removal percent of CV dye was augmented and reached a maximum value of 91.56% with increasing IDA concentration up to 0.15 M. Moreover, the experimental data were well-fitted both Langmuir and Freundlich isotherms with a maximum adsorption capacity of 107.52 mg/g. while the adsorption process was obeyed the pseudo-second order kinetic model. The developed adsorbent displayed respectable reusability after five sequential cycles and exhibited higher adsorption ability towards cationic CV dye compared to cationic methylene blue (MB) and anionic methyl orange (MO) dyes. Therefore, IDA@CMC-PBQ adsorbent could be effectually used as a convenient and reusable adsorbent for removing cationic dyes from their aqueous solutions.